The use of electrode separation members or "separators" in multi-electrode storage batteries is generally well-known, and these separators have been used, for example, in alkaline storage batteries employed in light-weight high-energy aerospace applications. Various recent studies in this art have shown that a principal limitation on the ability to manufacture high energy alkaline storage batteries lies in the design of the battery separator.
Typical alkaline storage batteries which have been used in certain aerospace applications, i.e., batteries such as nickel-cadmium and the higher energy nickel-hydrogen (NiH.sub.2) batteries, require separators which have at least several of the following characteristics: good chemical stability against the electroyte (generally an aqueous potassium hydroxide solution (KOH)), good mechanical strength, good wettability in the electrolyte, good electrolyte retention, good gas permeability through the battery separator, good electrolyte reservoir capability and a high melting point.
Previously, battery separators fabricated from materials such as asbestos, polypropylene, nylon, and various fibrous materials reinforced with polypropylene oxide, and zirconium oxide-yttrium oxide ceramic cloths have been used in space battery applications, but have not been found to be totally satisfactory in meeting many or all of the above described mechanical and electrical properties set forth with respect to separators for high energy nickel-cadmium and nickel-hydrogen batteries.